US Bridges

Back Loop RD over Montana Creek

Good

Juneau City and Borough, Alaska · Mile Point 4.5 · Structure no. 0264

Built
1985
40 years old
Condition
Good
inspected June 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
81 ft
1 main span
Daily traffic
2,770
2020 count
Owner
State
State Highway Agency

About this bridge

Back Loop RD over Montana Creek is a prestressed concrete stringer/multi-beam or girder carrying Back Loop RD over Montana Creek in Juneau City and Borough, Alaska. It was built in 1985, so it is 40 years old, older than the Alaska average of 35.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 2,770 vehicles a day, roughly 6% of them trucks, projected to reach 8,370 by 2039. The structure is 81 ft (24.7 m) long and 46 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesBack Loop RD
CrossesMontana Creek
LocationMile Point 4.5
RouteState Highway 966
CountyJuneau City and Borough
StateAlaska
Coordinates58.3975, -134.6109
Functional classUrban Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating98.1 US tons
Inventory rating44.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length81 ft (24.7 m)
Longest span78 ft (23.8 m)
Deck width46 ft (14 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,770 (2020)
Projected traffic8,370 by 2039
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed9.9 mi (16 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Back Loop RD over Montana Creek built?

It was built in 1985, making it 40 years old in 2025.

What condition is Back Loop RD over Montana Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in June 2023.

How much traffic does Back Loop RD over Montana Creek carry?

About 2,770 vehicles per day (2020 count), of which roughly 6% are trucks.

How long is Back Loop RD over Montana Creek?

The structure is 81 ft (24.7 m) long with a longest span of 78 ft (23.8 m) and a deck 46 ft wide.

Who owns Back Loop RD over Montana Creek?

It is owned by the State Highway Agency.